Iranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRNashrieh Shimi va Mohandesi Shimi Iran1022-776832420131201Synthesis of Low Density Silica Gel Using of Super Critical LiquidsSynthesis of Low Density Silica Gel Using of Super Critical Liquids1165547FAEbrahim BakhtiyaridoostInorganic Chemistry Research Group, Sharif University of Technology Branch, Iranian Academic Center for Education Culture and Research (ACECR), P.O. Box 13445-686Aliasghar EhteshamiInorganic Chemistry Research Group, Sharif University of Technology Branch, Iranian Academic Center for Education Culture and Research (ACECR), P.O. Box 13445-686Ghais RakhshanInorganic Chemistry Research Group, Sharif University of Technology Branch, Iranian Academic Center for Education Culture and Research (ACECR), P.O. Box 13445-686Asghar KaramiInorganic Chemistry Research Group, Sharif University of Technology Branch, Iranian Academic Center for Education Culture and Research (ACECR), P.O. Box 13445-686Journal Article20140130<em>Silica gel with low density can be prepared via various methods. According to abundance and low price, using sodium silicate as a silicon source in order to prepare initial seeds is one of the suitable and native methods. In this research, a suitable method based on the cheap raw materials and the ease of preparation was selected. In this method, as in the conventional one, primarily hydrosol was prepared through the reaction of sodium silicate and sulfuric acid. Then after conducting varius tests, the effective factors in reduction of the silica gel density such as: the time of rapid setting, alkalinizing the washing medium of the hydrogel, using solvents with low surface tension to prepare alcogel or acetogel, and curing them in the critical point temperature and pressure of the mentioned solvents were studied. Finally, a product with 0.18 g/cm<sup>3</sup> density, 7.5% adsorption capacity in 60% relative humidity, 17 micron particle size and 230 m<sup>2</sup>/g surface area at super critical point of aceton, was synthesized.</em><em>Silica gel with low density can be prepared via various methods. According to abundance and low price, using sodium silicate as a silicon source in order to prepare initial seeds is one of the suitable and native methods. In this research, a suitable method based on the cheap raw materials and the ease of preparation was selected. In this method, as in the conventional one, primarily hydrosol was prepared through the reaction of sodium silicate and sulfuric acid. Then after conducting varius tests, the effective factors in reduction of the silica gel density such as: the time of rapid setting, alkalinizing the washing medium of the hydrogel, using solvents with low surface tension to prepare alcogel or acetogel, and curing them in the critical point temperature and pressure of the mentioned solvents were studied. Finally, a product with 0.18 g/cm<sup>3</sup> density, 7.5% adsorption capacity in 60% relative humidity, 17 micron particle size and 230 m<sup>2</sup>/g surface area at super critical point of aceton, was synthesized.</em>https://www.nsmsi.ir/article_5547_78fe5edce929fdf662278dcc807766d6.pdfIranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRNashrieh Shimi va Mohandesi Shimi Iran1022-776832420131201Chemical Vapor Deposition of Ruthenium Nano Layer on Co/Al2O3 Catalyst for Fischer-Tropsch Synthesis Using Ru3(CO)12 PrecursorChemical Vapor Deposition of Ruthenium Nano Layer on Co/Al2O3 Catalyst for Fischer-Tropsch Synthesis Using Ru3(CO)12 Precursor17325548FAMohammad Javad ParnianCatalysis and Nanostructured Materials Laboratory, School of Chemical Engineering, University of Tehran,
P.O. Box 11155-5463 Tehran, I.R. IRANYadollah MortazaviCatalysis and Nanostructured Materials Laboratory, School of Chemical Engineering, University of Tehran,
P.O. Box 11155-5463 Tehran, I.R. IRANAli Taheri NajafabadiCatalysis and Nanostructured Materials Laboratory, School of Chemical Engineering, University of Tehran,
P.O. Box 11155-5463 Tehran, I.R. IRANAbbas Ali KhodadadiCatalysis and Nanostructured Materials Laboratory, School of Chemical Engineering, University of Tehran,
P.O. Box 11155-5463 Tehran, I.R. IRANJournal Article20121027<em>In present investigation, ruthenium was deposited on cobalt supported alumina catalyst by Chemical Vapor Deposition (CVD) of Ru<sub>3</sub>(CO)<sub>12</sub> for Fischer-Tropsch Synthesis (FTS). The 15.0 wt% Co/γ-Al<sub>2</sub>O<sub>3</sub> catalyst was prepared by wet impregnation of cobalt nitrate aqueous solution, and then dried and calcined at 400<sup>o</sup>C for 4 h. To optimize the CVD operating conditions in which Ru<sub>3</sub>(CO)<sub>12</sub> starts to decompose on surface of the catalyst, the decomposition products of the CVD processwere passed through a gas cell of FT-IR. In a specific temperature range, ruthenium deposited selectively on the surface of cobalt active phase.The CVD of ruthenium onto Co/γ-Al<sub>2</sub>O<sub>3</sub> catalyst increased the catalyst reducibility which in turnled to a higher CO hydrogenation activity in FTS process. Furthermore, the promoted cobalt catalyst showed a better selectivity towards heavy hydrocarbons than the reference unpromoted catalyst. The effects of temperature (210<sup>o</sup>C-240<sup>o</sup>C) and H<sub>2</sub></em><em>/CO ratio (1-3) for all catalysts were examined. For the all operating conditions, the promoted catalyst performed much better than the unpromoted catalyst.</em><em>In present investigation, ruthenium was deposited on cobalt supported alumina catalyst by Chemical Vapor Deposition (CVD) of Ru<sub>3</sub>(CO)<sub>12</sub> for Fischer-Tropsch Synthesis (FTS). The 15.0 wt% Co/γ-Al<sub>2</sub>O<sub>3</sub> catalyst was prepared by wet impregnation of cobalt nitrate aqueous solution, and then dried and calcined at 400<sup>o</sup>C for 4 h. To optimize the CVD operating conditions in which Ru<sub>3</sub>(CO)<sub>12</sub> starts to decompose on surface of the catalyst, the decomposition products of the CVD processwere passed through a gas cell of FT-IR. In a specific temperature range, ruthenium deposited selectively on the surface of cobalt active phase.The CVD of ruthenium onto Co/γ-Al<sub>2</sub>O<sub>3</sub> catalyst increased the catalyst reducibility which in turnled to a higher CO hydrogenation activity in FTS process. Furthermore, the promoted cobalt catalyst showed a better selectivity towards heavy hydrocarbons than the reference unpromoted catalyst. The effects of temperature (210<sup>o</sup>C-240<sup>o</sup>C) and H<sub>2</sub></em><em>/CO ratio (1-3) for all catalysts were examined. For the all operating conditions, the promoted catalyst performed much better than the unpromoted catalyst.</em>https://www.nsmsi.ir/article_5548_98ac97dba215c2df7017e3cc61998d3e.pdfIranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRNashrieh Shimi va Mohandesi Shimi Iran1022-776832420131201Measurement of Glutamate Using Biosensor Based on Vertically Aligned Carbon NanotubesMeasurement of Glutamate Using Biosensor Based on Vertically Aligned Carbon Nanotubes33365550FAAzam GholizadehInstitute for Nanoscience and Nanotechnology (INST), Sharif University of Technology, Tehran, I.R. IRANSaeed ShahrokhianInstitute for Nanoscience and Nanotechnology (INST), Sharif University of Technology, Tehran, I.R. IRANAzam Iraji ZadInstitute for Nanoscience and Nanotechnology (INST), Sharif University of Technology, Tehran, I.R. IRANShamsoddin MohajerzadehThin Film and Nano-electronic Laboratory, Nano-electronic Center of Excellence,
Department of Electrical and Computer Engineering, University of Tehran, Tehran, I.R. IRANManouchehr VosoughiChemical & Petroleum Engineering Department, Sharif University of Technology Tehran, I.R. IRANJournal Article20120902<em>A sensitive glutamate biosensor is prepared based on glutamate dehydrogenase/vertically aligned carbon nanotubes (GLDH, VACNTs). Vertically aligned carbon nanotubes were grown on a silicon substrate by Direct Current Plasma Enhanced Chemical Vapor Deposition (DC-PECVD) method. Glutamate dehydrogenase covalently attached on tip of VACNTs. The electrochemical performance of the electrode for detection of glutamate was investigated by cyclic and differential pulse voltammetry. The linear calibration curve of the concentration of glutamate versus peak current is investigated in a wide range of 0.1–500 </em><em>m</em><em>M. The mediator-less biosensor has a low detection limit of 57 nM and two linearranges of 0.1–20 </em><em>m</em><em>M with a sensitivity of 0.976 mA/mM cm<sup>2</sup> and 20–300 </em><em>m</em><em>M with a sensitivity of 0.182 mA/mM</em><em>.</em><em>cm<sup>2</sup>. The effects of the other biological compounds on the voltammetric behavior of the prepared biosensor and its response stability are investigated. The results are demonstrated that the GLDH/VACNTs electrode even without electron mediator is a suitable basic electrode for detection of glutamate.</em><em>A sensitive glutamate biosensor is prepared based on glutamate dehydrogenase/vertically aligned carbon nanotubes (GLDH, VACNTs). Vertically aligned carbon nanotubes were grown on a silicon substrate by Direct Current Plasma Enhanced Chemical Vapor Deposition (DC-PECVD) method. Glutamate dehydrogenase covalently attached on tip of VACNTs. The electrochemical performance of the electrode for detection of glutamate was investigated by cyclic and differential pulse voltammetry. The linear calibration curve of the concentration of glutamate versus peak current is investigated in a wide range of 0.1–500 </em><em>m</em><em>M. The mediator-less biosensor has a low detection limit of 57 nM and two linearranges of 0.1–20 </em><em>m</em><em>M with a sensitivity of 0.976 mA/mM cm<sup>2</sup> and 20–300 </em><em>m</em><em>M with a sensitivity of 0.182 mA/mM</em><em>.</em><em>cm<sup>2</sup>. The effects of the other biological compounds on the voltammetric behavior of the prepared biosensor and its response stability are investigated. The results are demonstrated that the GLDH/VACNTs electrode even without electron mediator is a suitable basic electrode for detection of glutamate.</em>https://www.nsmsi.ir/article_5550_eae382e8654d1ab238e92d201736a967.pdfIranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRNashrieh Shimi va Mohandesi Shimi Iran1022-776832420131201A New Kinetic Model Development and Modeling of Hydrotreating Reaction for Vacuum Gas Oil (VGO)A New Kinetic Model Development and Modeling of Hydrotreating Reaction for Vacuum Gas Oil (VGO)37445553FAMaryam BozorgniaRefining Division, Research Institute of Petroleum Industry (RIPI), P.O. Box 14665-137 Tehran, I.R. IRANJafar Towfighi DarianDepartment of Chemical Engineering, Tarbiat Modares University,
P.O. Box 14115-143 Tehran, I.R. IRANJournal Article20120512<em>In this work a novel Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic equation has been proposed for hydrodesulfurization (HDS) and used an unusual hydrodenitrogenation (HDN) kinetic equation. These equations include inhibitive effect of nitrogenous compounds (basic and nonbasic) on the HDS reaction and the activating effect of H<sub>2</sub>S concentration on HDN reactions (basic and nonbasic). Three phase reactor model that incorporates the effect of hydrodynamics has been developed. The concentration profiles obtained using the proposed kinetics for hydrotreating reactions were compared with other kinetic models and pilot plant experimental data available in the literature. The predicted value showed a very good agreement with the experimental data. The average absolute error for all predictions is <1.5% while the published value in the literature is <2%.</em><em>In this work a novel Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic equation has been proposed for hydrodesulfurization (HDS) and used an unusual hydrodenitrogenation (HDN) kinetic equation. These equations include inhibitive effect of nitrogenous compounds (basic and nonbasic) on the HDS reaction and the activating effect of H<sub>2</sub>S concentration on HDN reactions (basic and nonbasic). Three phase reactor model that incorporates the effect of hydrodynamics has been developed. The concentration profiles obtained using the proposed kinetics for hydrotreating reactions were compared with other kinetic models and pilot plant experimental data available in the literature. The predicted value showed a very good agreement with the experimental data. The average absolute error for all predictions is <1.5% while the published value in the literature is <2%.</em>https://www.nsmsi.ir/article_5553_1e756359b8ab272d06a217eaa2330e48.pdfIranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRNashrieh Shimi va Mohandesi Shimi Iran1022-776832420131201Experimental Investigation of Coating Process of Sodium Percarbonate Powder by Sodium Silicate in Fluidized BedExperimental Investigation of Coating Process of Sodium Percarbonate Powder by Sodium Silicate in Fluidized Bed45585554FAMehdi ArdjmandChemical Engineering Department, Tehran South Branch, Islamic Azad University, Tehran, I.R. IRANSeyed Hasan AlhoseiniMetallic Material Processing Research Group, Tehran University Branch,
Iranian Academic Center for Education Culture and Research (ACECR), Tehran, I.R. IRANSeyed Hadi SeyedinMetallic Material Processing Research Group, Tehran University Branch,
Iranian Academic Center for Education Culture and Research (ACECR), Tehran, I.R. IRANJournal Article20120512<em>In this paper, particles coating system in fluid bed have been studied. This system includes two process of coating and drying in the bed and</em><em> used for coating of sodium per carbonate particles by liquid sodium silicate. This is a top spray coating system and batch type. Response Surface Method (RSM) was applied for experiment design by means of Minitab software, version 15. The fluidization hydrodynamics of particles and air flow was studied. The optimum operating conditions was determined. The effect of particles fluidization height, air and liquid flow rates on coating efficiency was investigated. The experimental results showed that, the mass of particles coating, was proportional to the liquid value and indirectly to the air flow rates. Experimental correlation of coating mass is proportional with fluidized air and liquid flow rates and atomization air flow. Also RSM tables and contours for process optimization, for investigation of system performance were derived. The result of fluidized height of particles based on time and coating mass with different air and liquid flow rates for the best case of particles coating was calculated and investigated and optimized coating information was obtained.</em><em>In this paper, particles coating system in fluid bed have been studied. This system includes two process of coating and drying in the bed and</em><em> used for coating of sodium per carbonate particles by liquid sodium silicate. This is a top spray coating system and batch type. Response Surface Method (RSM) was applied for experiment design by means of Minitab software, version 15. The fluidization hydrodynamics of particles and air flow was studied. The optimum operating conditions was determined. The effect of particles fluidization height, air and liquid flow rates on coating efficiency was investigated. The experimental results showed that, the mass of particles coating, was proportional to the liquid value and indirectly to the air flow rates. Experimental correlation of coating mass is proportional with fluidized air and liquid flow rates and atomization air flow. Also RSM tables and contours for process optimization, for investigation of system performance were derived. The result of fluidized height of particles based on time and coating mass with different air and liquid flow rates for the best case of particles coating was calculated and investigated and optimized coating information was obtained.</em>https://www.nsmsi.ir/article_5554_3b63d5437832d14e9a68f00e235e3225.pdfIranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRNashrieh Shimi va Mohandesi Shimi Iran1022-776832420131201Preparation and Study on the Properties of LDPE-Thermoplastic Starch Blends; Part I: Effect of PE-g-MA on the Mechanical Properties and Flow BehaviorPreparation and Study on the Properties of LDPE-Thermoplastic Starch Blends; Part I: Effect of PE-g-MA on the Mechanical Properties and Flow Behavior59695557FAMaryam SabetzadehPolymer Group, Chemical Engineering Department, Isfahan University of Technology,
P.O. Box 84156-83111 Isfahan, I.R. IRANRouhollah BagheriPolymer Group, Chemical Engineering Department, Isfahan University of Technology,
P.O. Box 84156-83111 Isfahan, I.R. IRANMahmood MassomiPolymer Group, Chemical Engineering Department, Isfahan University of Technology,
P.O. Box 84156-83111 Isfahan, I.R. IRANJournal Article20111215<em>In this work, effect of maleic anhydride grafted- LDPE (PE-g-MA) on the mechanical, morphology and flow behavior of biodegradable LDPE-thermoplastic corn starch (TPS) blends were investigated. TPS was prepared by mixing neat starch and glycerol (35wt. %) at room temperature. The mixture then was melt-compounded using an internal mixer at 140<sup>o</sup>C, rotor speed of 60 rpm for 8 minutes. LDPE-TPS blends containing different contents of TPS (0-40wt. %) with (3wt. %) and without the addition of PE-g-MA, were prepared using a single-screw extruder. Surface morphology of the prepared blends was investigated by Scanning Electron Microscopy (SEM). Also, mechanical properties and flow behavior of the prepared samples were carried out by means of related standard test methods. Scanning electron micrographs of the samples show improvement in dispersion of the starch particles in LDPE matrix in the presence of PE-g-MA as a compatibilizer. Also, the results of mechanical properties indicate that as TPS concentration increases, the ultimate tensile strength, elongation at break, Young’s modulus and relative impact strength of the blends decrease. However, the compatibilized blends represent higher mechanical properties than the blends without any compatibilizer. Furthermore, the addition of starch to LDPE decreases the melt flow index values of the samples and subsequently increases their apparent viscosity.The results of rheological tests also indicate that as shear rate increases, the apparent viscosity of the samples decreases (shear thinning).</em><em>In this work, effect of maleic anhydride grafted- LDPE (PE-g-MA) on the mechanical, morphology and flow behavior of biodegradable LDPE-thermoplastic corn starch (TPS) blends were investigated. TPS was prepared by mixing neat starch and glycerol (35wt. %) at room temperature. The mixture then was melt-compounded using an internal mixer at 140<sup>o</sup>C, rotor speed of 60 rpm for 8 minutes. LDPE-TPS blends containing different contents of TPS (0-40wt. %) with (3wt. %) and without the addition of PE-g-MA, were prepared using a single-screw extruder. Surface morphology of the prepared blends was investigated by Scanning Electron Microscopy (SEM). Also, mechanical properties and flow behavior of the prepared samples were carried out by means of related standard test methods. Scanning electron micrographs of the samples show improvement in dispersion of the starch particles in LDPE matrix in the presence of PE-g-MA as a compatibilizer. Also, the results of mechanical properties indicate that as TPS concentration increases, the ultimate tensile strength, elongation at break, Young’s modulus and relative impact strength of the blends decrease. However, the compatibilized blends represent higher mechanical properties than the blends without any compatibilizer. Furthermore, the addition of starch to LDPE decreases the melt flow index values of the samples and subsequently increases their apparent viscosity.The results of rheological tests also indicate that as shear rate increases, the apparent viscosity of the samples decreases (shear thinning).</em>https://www.nsmsi.ir/article_5557_da31b81e93603197ff8c2d6ff9d4f14b.pdfIranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRNashrieh Shimi va Mohandesi Shimi Iran1022-776832420131201Development of High-Speed Photography and Image Processing Method for the Characterization of Bubbles in a Bubble ColumnDevelopment of High-Speed Photography and Image Processing Method for the Characterization of Bubbles in a Bubble Column71805565FAHamid AsadiFaculty of Chemical & Petroleum and Gas Engineering, Semnan University,
P.O. Box. 35131-19111 Semnan, I.R. IRANFaramarz HormoziFaculty of Chemical & Petroleum and Gas Engineering, Semnan University,
P.O. Box. 35131-19111 Semnan, I.R. IRANJournal Article20110303<em>In the present </em><em>research, </em><em>a</em><em> square bubble column has experimentally been utilized in order to quantify the important hydrodynamic properties of bubbly liquid/gas two phase flows, such as bubble velocity and diameter, flow pattern</em><em> as well as </em><em>oscillation</em><em>frequency of</em><em>the gas phase via the high-speed</em><em> video recorder. Results were then processed using new techniques of image processing.</em><em> The column was fabricated from plexy-glass which was dimensionally 205120cm (cross sectionheight). Results indicated that gas superficial velocity varied from 0.1 to 0.7 cm/s. Three cameras with different speeds were employed (20, 500 and 600 frames per second) to evaluate the bubble characteristics and MATLAB 7.4 (2007a) was used for image analysis. Oscillation frequency of gas phase was obtained using a new method with accuracy close to 95%. At coalescence condition, Mean Sauter Diameter (MSD) of bubbles was calculated with accuracy of about 99.8%. For the first time, bubble velocity was computed by "minimum distance with upper limit" method in the bubble column.</em><em>In the present </em><em>research, </em><em>a</em><em> square bubble column has experimentally been utilized in order to quantify the important hydrodynamic properties of bubbly liquid/gas two phase flows, such as bubble velocity and diameter, flow pattern</em><em> as well as </em><em>oscillation</em><em>frequency of</em><em>the gas phase via the high-speed</em><em> video recorder. Results were then processed using new techniques of image processing.</em><em> The column was fabricated from plexy-glass which was dimensionally 205120cm (cross sectionheight). Results indicated that gas superficial velocity varied from 0.1 to 0.7 cm/s. Three cameras with different speeds were employed (20, 500 and 600 frames per second) to evaluate the bubble characteristics and MATLAB 7.4 (2007a) was used for image analysis. Oscillation frequency of gas phase was obtained using a new method with accuracy close to 95%. At coalescence condition, Mean Sauter Diameter (MSD) of bubbles was calculated with accuracy of about 99.8%. For the first time, bubble velocity was computed by "minimum distance with upper limit" method in the bubble column.</em>https://www.nsmsi.ir/article_5565_8fa4309d2bb95480c98057a39552c156.pdfIranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRNashrieh Shimi va Mohandesi Shimi Iran1022-776832420131201Flotation of Chalcopyrite Fine Particles in the Presence of Hydrodynamic Cavitation NanobybblesFlotation of Chalcopyrite Fine Particles in the Presence of Hydrodynamic Cavitation Nanobybbles81915566FARahman AhmadiDepartment of Mineral Processing Engineering, Tarbiat Modares University (TMU),
P.O. Box 111-14115 Tehran, I.R. IRANAhmad Khodadadi DarbanDepartment of Mineral Processing Engineering, Tarbiat Modares University (TMU),
P.O. Box 111-14115 Tehran, I.R. IRANMahmoud AbdollahyDepartment of Mineral Processing Engineering, Tarbiat Modares University (TMU),
P.O. Box 111-14115 Tehran, I.R. IRANJournal Article20130707<em>In this paper, the effect of presence of nano-microbubbles on flotation recovery of chalcopyrite fine particles (-38+5µm) has been studied. Comparative flotation tests were performed both in the presence and absence of nano-microbubbles (conventional flotation) to evaluate recovery changes of chalcopyrite. Methyl IsoButyl Carbinol (MIBC) was used as frother and Potassium Amyl Xanthate (KAX) as collector at pH= 10. Nano-microbubbles were generated using a nano-microbubble generator based on cavitation phenomenon in venturi tubes. Changes in size distribution, zeta potential and stability of nano-microbubbles were measured as a function of time. Results showed that the interval between generation time and 10 minutes after that, simultaneous with reduction of the absolute value of zeta potential increased the average size of nano-microbubbles from 358 nm to 13.24 μm. The results in the presence of nano-microbubbles showed increased flotation recovery of chalcopyrite fines by 16-21% and reduction of chemicals reagent (up to 75% of collector and 50% of frother). In addition, the effect of nano-microbubbles on promoting the recovery of ultrafine particles (-14.36+5 μm), has been higher than fine particles (+14.36-38 μm).</em><em>In this paper, the effect of presence of nano-microbubbles on flotation recovery of chalcopyrite fine particles (-38+5µm) has been studied. Comparative flotation tests were performed both in the presence and absence of nano-microbubbles (conventional flotation) to evaluate recovery changes of chalcopyrite. Methyl IsoButyl Carbinol (MIBC) was used as frother and Potassium Amyl Xanthate (KAX) as collector at pH= 10. Nano-microbubbles were generated using a nano-microbubble generator based on cavitation phenomenon in venturi tubes. Changes in size distribution, zeta potential and stability of nano-microbubbles were measured as a function of time. Results showed that the interval between generation time and 10 minutes after that, simultaneous with reduction of the absolute value of zeta potential increased the average size of nano-microbubbles from 358 nm to 13.24 μm. The results in the presence of nano-microbubbles showed increased flotation recovery of chalcopyrite fines by 16-21% and reduction of chemicals reagent (up to 75% of collector and 50% of frother). In addition, the effect of nano-microbubbles on promoting the recovery of ultrafine particles (-14.36+5 μm), has been higher than fine particles (+14.36-38 μm).</em>https://www.nsmsi.ir/article_5566_61d863350766a0b8be3c79a9a35ceb88.pdfIranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRNashrieh Shimi va Mohandesi Shimi Iran1022-776832420131201Thermo Economic Modeling and Parametric Analysis of a PSOFC/GT Hybrid CycleThermo Economic Modeling and Parametric Analysis of a PSOFC/GT Hybrid Cycle931035567FAGhasem ArabDepartment of Energy Engineering, College of Energy and Environment,
Tehran Science and Research Branch, Islamic Azad University, Tehran, I.R. IRANHossein GhadamianDepartment of Energy, Materials and Energy Research Center (MERC), P.O. Box 14155-4777 Tehran, I.R. IRANJournal Article20130308<em>In this research, the thermo economic analysis of a PSOFC/GT hybrid cycle was taking</em><em> place regarding a sustainable approach. Initially, the proposed cycle was accurately introduced and then the modeling methodology was presented. Furthermore, the cycle simulation was presented with the development of a thermodynamic model in EES software based on the mass, energy and economic equations, those were solved simultaneously. With introducing electrical and overall efficiencies, a comprehensive analysis of thermodynamics was done, which was contributed to a dynamic economic model, which was proposed and analyzed in after-steps. In order to determine effects of change in main parameters, a parametric study was prepared. By these means, the results show that the electrical efficiency of 61.3 % and overall efficiency of 77.65 % are achievable within 1962 kW net output power, where, HRSG heat recovery capacity is equal to 436.8 kW and HPR was calculated 22.27 %. This cycle with producing 310.9 g/kWh CO<sub>2</sub>, reduces the CO<sub>2</sub> emissions by 30.3 % comparing with the conventional gas fired combined cycles.</em><em>In this research, the thermo economic analysis of a PSOFC/GT hybrid cycle was taking</em><em> place regarding a sustainable approach. Initially, the proposed cycle was accurately introduced and then the modeling methodology was presented. Furthermore, the cycle simulation was presented with the development of a thermodynamic model in EES software based on the mass, energy and economic equations, those were solved simultaneously. With introducing electrical and overall efficiencies, a comprehensive analysis of thermodynamics was done, which was contributed to a dynamic economic model, which was proposed and analyzed in after-steps. In order to determine effects of change in main parameters, a parametric study was prepared. By these means, the results show that the electrical efficiency of 61.3 % and overall efficiency of 77.65 % are achievable within 1962 kW net output power, where, HRSG heat recovery capacity is equal to 436.8 kW and HPR was calculated 22.27 %. This cycle with producing 310.9 g/kWh CO<sub>2</sub>, reduces the CO<sub>2</sub> emissions by 30.3 % comparing with the conventional gas fired combined cycles.</em>https://www.nsmsi.ir/article_5567_9bfe49df51d5e8a02f2bd714a2143cdb.pdfIranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRNashrieh Shimi va Mohandesi Shimi Iran1022-776832420131201Biomass Separation in Moving Bed Biofilm Reactors with Innovative FiltersBiomass Separation in Moving Bed Biofilm Reactors with Innovative Filters1051175568FAElham AshrafiChemical and Petroleum Engineering Department, Sharif University of Technology, Tehran, I.R. IRANSeyed Mehdi BorgheiChemical and Petroleum Engineering Department, Sharif University of Technology, Tehran, I.R. IRANAli GharaeiChemical and Petroleum Engineering Department, Biochemical and Bioenvironmental Engineering Research Center (B.B.R.C), Sharif University of Technology, Tehran, I.R. IRANJournal Article20110124<em>Membrane bioreactors (MBR Process) are now considered as one of the main new processes in wastewater treatment. Membranes used for wastewater purification are fabricated from different oil based polymers including</em><em>PVC, polysulphonates, polyamides and many other synthetic polymers. Fabrication technology is advanced and only in possession of very few multinational companies. For these reasons, membranes are expensive and not easily available. This study was carried out to test an innovative, locally made filter element for separation of flocks in an MBBR reactor. This innovative filter is seen as a viable replacement to a conventional settling tank that may be even as effective as synthetic polymer membranes. The filter’s element was made very cheaply and had important advantages in installing and operation. Experiments were carried out using a laboratory scale MBBR unit as the biological aerated reactor, fixed with filter elements inside aeration chamber, similar to a MBR installation. The filter elements consisted of 3 plastic filter tubes with perforations and covered with dense cotton-polyester yarns and were placed inside the aeration chamber. The bioreactor was run over a period of 10 months with usual conditions resembling a real biological wastewater treatment unit. Reactor performance was measured regularly and the results indicated that 99% of suspended solids are separated under normal conditions. Filter clogging, a very familiar problem with membrane bioreactors, was not seen as an obstacle in bioreactor operation. Outflow TSS was lower than 12 mg/L, while overall organic removal was over 95 percent. Next set of experiments were carried with fewer filter elements and higher value of TSS in the effluent was observed, indicating that filters surface area (or number of filter elements) have a profound effect on treatment efficiency as could be well expected. Overall the experiments indicated that locally made MBR can easily be applied in existing plants, saving money and operational difficulties.</em> <em>Membrane bioreactors (MBR Process) are now considered as one of the main new processes in wastewater treatment. Membranes used for wastewater purification are fabricated from different oil based polymers including</em><em>PVC, polysulphonates, polyamides and many other synthetic polymers. Fabrication technology is advanced and only in possession of very few multinational companies. For these reasons, membranes are expensive and not easily available. This study was carried out to test an innovative, locally made filter element for separation of flocks in an MBBR reactor. This innovative filter is seen as a viable replacement to a conventional settling tank that may be even as effective as synthetic polymer membranes. The filter’s element was made very cheaply and had important advantages in installing and operation. Experiments were carried out using a laboratory scale MBBR unit as the biological aerated reactor, fixed with filter elements inside aeration chamber, similar to a MBR installation. The filter elements consisted of 3 plastic filter tubes with perforations and covered with dense cotton-polyester yarns and were placed inside the aeration chamber. The bioreactor was run over a period of 10 months with usual conditions resembling a real biological wastewater treatment unit. Reactor performance was measured regularly and the results indicated that 99% of suspended solids are separated under normal conditions. Filter clogging, a very familiar problem with membrane bioreactors, was not seen as an obstacle in bioreactor operation. Outflow TSS was lower than 12 mg/L, while overall organic removal was over 95 percent. Next set of experiments were carried with fewer filter elements and higher value of TSS in the effluent was observed, indicating that filters surface area (or number of filter elements) have a profound effect on treatment efficiency as could be well expected. Overall the experiments indicated that locally made MBR can easily be applied in existing plants, saving money and operational difficulties.</em> https://www.nsmsi.ir/article_5568_85ea2c266b09325f2b43c1ebbca22cbf.pdf